Method and apparatus for reduced capability terminal to determine intra-frequency cell reselection parameter in mobile wireless communication system

ABSTRACT

A method and apparatus for selecting a NR cell in a mobile communication system are provided. Method for selecting a NR cell includes selecting, by a terminal, a first cell, performing, by the terminal a first operation group if the terminal fails to acquire MIB in the first cell and performing, by the terminal a second operation group if the terminal succeeds to acquire MIB and SIB1 in the first cell and the MIB includes cellBarred set to barred and the SIB1 includes a intraFreqReselection set to NotAllowed.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application is a Continuation Application of U.S. patentapplication Ser. No. 17/881,535, filed on Aug. 4, 2022, pending at thetime of filing of the present patent application, which claims thebenefit of priority based on Korean Patent Application No.10-2021-0119149, filed on Sep. 7, 2021, the disclosure of which isincorporated herein by reference in its entirety.

BACKGROUND Technical Field

The present disclosure relates to a method and apparatus for a terminalwith reduced capability in a wireless communication system to obtainsystem information and access a New Radio cell.

Related Art

To meet the increasing demand for wireless data traffic since thecommercialization of 4th generation (4G) communication systems, the 5thgeneration (5G) system is being developed. For the sake of high, 5Gsystem introduced millimeter wave (mmW) frequency bands (e. g. 60 GHzbands). In order to increase the propagation distance by mitigatingpropagation loss in the 5G communication system, various techniques areintroduced such as beamforming, massive multiple-input multiple output(MIMO), full dimensional MIMO (FD-MIMO), array antenna, analogbeamforming, and large-scale antenna. In addition, base station isdivided into a central unit and plurality of distribute units for betterscalability. To facilitate introduction of various services, 5Gcommunication system targets supporting higher data rate and smallerlatency.

Various attempts are being made to apply the 5G communication system tothe IoT network. For example, 5G communication such as sensor network,machine to machine communication (M2M), and machine type communication(MTC) is being implemented by techniques such as beam forming, MIMO, andarray antenna.

The terminal performing the MTC communication requires only limitedperformance compared to a general smart phone, and a terminal havingonly reduced capability for MTC communication is referred to as a RedCapUE. In order to efficiently support RedCap UE in a mobile communicationsystem, there is a need to introduce a new technology to an existingmobile communication system.

SUMMARY

Aspects of the present disclosure are to address the various methods ofimplementing NR cell access in mobile communication system. Accordingly,an aspect of the present disclosure is to provide a method and anapparatus for selecting, by a terminal, a first cell, performing, by theterminal a first operation group if the terminal fails to acquire MIB inthe first cell and performing, by the terminal a second operation groupif the terminal succeeds to acquire MIB and SIB1 in the first cell andthe MIB includes cellBarred set to barred and the SIB1 includes aintraFreqReselection set to NotAllowed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a diagram illustrating the architecture of an 5G system and aNG-RAN to which the disclosure may be applied;

FIG. 1B is a diagram illustrating a wireless protocol architecture in an5G system to which the disclosure may be applied;

FIG. 2A is a diagram illustrating an example of a bandwidth part.

FIG. 2B is a diagram illustrating an example of a search space and acontrol resource set.

FIG. 3 is a diagram illustrating operations of a terminal and a basestation according to an embodiment of the present invention.

FIG. 4 is a flow diagram illustrating an operation of a terminal.

FIG. 5A is a block diagram illustrating the internal structure of a UEto which the disclosure is applied.

FIG. 5B is a block diagram illustrating the configuration of a basestation according to the disclosure.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present invention will be described indetail with reference to the accompanying drawings. In addition, in thedescription of the present invention, if it is determined that adetailed description of a related known function or configuration mayunnecessarily obscure the gist of the present invention, the detaileddescription thereof will be omitted. In addition, the terms to bedescribed later are terms defined in consideration of functions in thepresent invention, which may vary according to intentions or customs ofusers and operators. Therefore, the definition should be made based onthe content throughout this specification.

The terms used, in the following description, for indicating accessnodes, network entities, messages, interfaces between network entities,and diverse identity information is provided for convenience ofexplanation. Accordingly, the terms used in the following descriptionare not limited to specific meanings but may be replaced by other termsequivalent in technical meanings.

In the following descriptions, the terms and definitions given in the3GPP standards are used for convenience of explanation. However, thepresent disclosure is not limited by use of these terms and definitionsand other arbitrary terms and definitions may be employed instead.

Table 1 lists the acronyms used throughout the present disclosure.

TABLE 1 Acronym Full name 5GC 5G Core Network ACK Acknowledgement AMAcknowledged Mode AMF Access and Mobility Management Function ARQAutomatic Repeat Request AS Access Stratum ASN.1 Abstract SyntaxNotation One BSR Buffer Status Report BWP Bandwidth Part CA CarrierAggregation CAG Closed Access Group CG Cell Group C-RNTI Cell RNTI CSIChannel State Information DCI Downlink Control Information DRB (user)Data Radio Bearer DRX Discontinuous Reception HARQ Hybrid AutomaticRepeat Request IE Information element LCG Logical Channel Group MACMedium Access Control MIB Master Information Block NAS Non-AccessStratum NG-RAN NG Radio Access Network NR NR Radio Access PBRPrioritised Bit Rate PCell Primary Cell PCI Physical Cell IdentifierPDCCH Physical Downlink Control Channel PDCP Packet Data ConvergenceProtocol PDSCH Physical Downlink Shared Channel PDU Protocol Data UnitPHR Power Headroom Report PLMN Public Land Mobile Network PRACH PhysicalRandom Access Channel PRB Physical Resource Block PSS PrimarySynchronisation Signal PUCCH Physical Uplink Control Channel PUSCHPhysical Uplink Shared Channel RACH Random Access Channel RAN RadioAccess Network RAR Random Access Response RA-RNTI Random Access RNTI RATRadio Access Technology RB Radio Bearer RLC Radio Link Control RNARAN-based Notification Area RNAU RAN-based Notification Area Update RNTIRadio Network Temporary Identifier RRC Radio Resource Control RRM RadioResource Management RSRP Reference Signal Received Power RSRQ ReferenceSignal Received Quality RSSI Received Signal Strength Indicator SCellSecondary Cell SCS Subcarrier Spacing SDAP Service Data AdaptationProtocol SDU Service Data Unit SFN System Frame Number S-GW ServingGateway SI System Information SIB System Information Block SpCellSpecial Cell SRB Signalling Radio Bearer SRS Sounding Reference SignalSS Search Space SSB SS/PBCH block SSS Secondary Synchronisation SignalSUL Supplementary Uplink TM Transparent Mode UCI Uplink ControlInformation UE User Equipment UM Unacknowledged Mode CRP CellReselection Priority

Table 2 lists the terminologies and their definition used throughout thepresent disclosure.

TABLE 2 Terminology Definition Carrier frequency center frequency of thecell. Cell combination of downlink and optionally uplink resources. Thelinking between the carrier frequency of the downlink resources and thecarrier frequency of the uplink resources is indicated in the systeminformation transmitted on the downlink resources. Cell Group in dualconnectivity, a group of serving cells associated with either the MeNBor the SeNB. Cell reselection A process to find a better suitable cellthan the current serving cell based on the system information receivedin the current serving cell Cell selection A process to find a suitablecell either blindly or based on the stored information Cell ReselectionPriority of a carrier frequency regarding cell reselection. SystemPriority Information Block 2 and System Information Block 3 provide theCRP of the serving frequency and CRPs of inter-frequencies respectively.UE consider higher priority frequency for cell reselection if channelcondition of the frequency is better than a specific threshold even ifchannel condition of a lower priority frequency is better than that ofthe higher priority frequency. Dedicated Signalling sent on DCCH logicalchannel between the network and signalling a single UE. Field Theindividual contents of an information element are referred to as fields.Frequency layer set of cells with the same carrier frequency. Globalcell An identity to uniquely identifying an NR cell. It is consisted ofidentity cellIdentity and plmn-Identity of the first PLMN-Identity inplmn- IdentityList in SIB1. gNB node providing NR user plane and controlplane protocol terminations towards the UE, and connected via the NGinterface to the 5GC. Handover procedure that changes the serving cellof a UE in RRC_CONNECTED. Information A structural element containingsingle or multiple fields is referred element as information element. LThe Length field in MAC subheader indicates the length of thecorresponding MAC SDU or of the corresponding MAC CE LCID 6 bit logicalchannel identity in MAC subheader to denote which logical channeltraffic or which MAC CE is included in the MAC subPDU Logical channel alogical path between a RLC entity and a MAC entity. There are multiplelogical channel types depending on what type of information istransferred e.g. CCCH (Common Control Channel), DCCH (Dedicate ControlChannel), DTCH (Dedicate Traffic Channel), PCCH (Paging Control Channel)NR NR radio access PCell SpCell of a master cell group. registered PLMNPLMN which UE has registered to selected PLMN PLMN which UE has selectedto perform registration procedure equivalent PLMN PLMN which isequivalent to registered PLMN. UE is informed of list of EPLMNs by AMFduring registration procedure PLMN ID Check the process that checkswhether a PLMN ID is the RPLMN identity or an EPLMN identity of the UE.Primary Cell The MCG cell, operating on the primary frequency, in whichthe UE either performs the initial connection establishment procedure orinitiates the connection re-establishment procedure. Radio BearerLogical path between a PDCP entity and upper layer (i.e. SDAP entity orRRC) RLC bearer RLC and MAC logical channel configuration of a radiobearer in one cell group. RLC bearer The lower layer part of the radiobearer configuration comprising configuration the RLC and logicalchannel configurations. Serving Cell For a UE in RRC_CONNECTED notconfigured with CA/DC there is only one serving cell comprising of theprimary cell. For a UE in RRC_CONNECTED configured with CA/ DC the term‘serving cells’ is used to denote the set of cells comprising of theSpecial Cell(s) and all secondary cells. SpCell primary cell of a masteror secondary cell group. Special Cell For Dual Connectivity operationthe term Special Cell refers to the PCell of the MCG or the PSCell ofthe SCG, otherwise the term Special Cell refers to the PCell. SRBSignalling Radio Bearers” (SRBs) are defined as Radio Bearers (RBs) thatare used only for the transmission of RRC and NAS messages. SRB0 SRB0 isfor RRC messages using the CCCH logical channel SRB1 SRB1 is for RRCmessages (which may include a piggybacked NAS message) as well as forNAS messages prior to the establishment of SRB2, all using DCCH logicalchannel; SRB2 SRB2 is for NAS messages and for RRC messages whichinclude logged measurement information, all using DCCH logical channel.SRB2 has a lower priority than SRB1 and may be configured by the networkafter AS security activation; SRB3 SRB3 is for specific RRC messageswhen UE is in (NG)EN-DC or NR-DC, all using DCCH logical channel SRB4SRB4 is for RRC messages which include application layer measurementreporting information, all using DCCH logical channel. DCCH DCCH is alogical channel to transfer RRC messages after RRC connectionestablishment Suitable cell A cell on which a UE may camp. Followingcriteria apply The cell is part of either the selected PLMN or theregistered PLMN or PLMN of the Equivalent PLMN list The cell is notbarred The cell is part of at least one TA that is not part of the listof “Forbidden Tracking Areas for Roaming” (TS 22.011 [18]), whichbelongs to a PLMN that fulfils the first bullet above. The cellselection criterion S is fulfilled (i.e. RSRP and RSRQ are better thanspecific values

In the present invention, “trigger” or “triggered” and “initiate” or“initiated” may be used in the same meaning.

In the present invention, a terminal with reduced capability and RedCapUE may be used in the same meaning.

FIG. 1A is a diagram illustrating the architecture of an 5G system and aNG-RAN to which the disclosure may be applied.

5G system consists of NG-RAN 1A-01 and 5GC 1A-02. An NG-RAN node iseither:

-   -   a gNB, providing NR user plane and control plane protocol        terminations towards the UE; or    -   an ng-eNB, providing E-UTRA user plane and control plane        protocol terminations towards the UE.

The gNBs 1A-05 or 1A-06 and ng-eNBs 1A-03 or 1A-04 are interconnectedwith each other by means of the Xn interface. The gNBs and ng-eNBs arealso connected by means of the NG interfaces to the 5GC, morespecifically to the AMF (Access and Mobility Management Function) and tothe UPF (User Plane Function). AMF 1A-07 and UPF 1A-08 may be realizedas a physical node or as separate physical nodes.

A gNB 1A-05 or 1A-06 or an ng-eNBs 1A-03 or 1A-04 hosts the functionslisted below.

Functions for Radio Resource Management such as Radio Bearer Control,Radio Admission Control, Connection Mobility Control, Dynamic allocationof resources to UEs in uplink, downlink and sidelink (scheduling); and

IP and Ethernet header compression, uplink data decompression andencryption of user data stream; and

Selection of an AMF at UE attachment when no routing to an MME can bedetermined from the information provided by the UE; and

Routing of User Plane data towards UPF; and

Scheduling and transmission of paging messages; and

Scheduling and transmission of broadcast information (originated fromthe AMF or O&M); and

Measurement and measurement reporting configuration for mobility andscheduling; and

Session Management; and

QoS Flow management and mapping to data radio bearers; and

Support of UEs in RRC_INACTIVE state; and

Radio access network sharing; and

Tight interworking between NR and E-UTRA; and

Support of Network Slicing.

The AMF 1A-07 hosts the functions such as NAS signaling, NAS signalingsecurity, AS security control, SMF selection, Authentication, Mobilitymanagement and positioning management.

The UPF 1A-08 hosts the functions such as packet routing and forwarding,transport level packet marking in the uplink, QoS handling and thedownlink, mobility anchoring for mobility etc.

FIG. 1B is a diagram illustrating a wireless protocol architecture in an5G system to which the disclosure may be applied.

User plane protocol stack consists of SDAP 1B-01 or 1B-02, PDCP 1B-03 or1B-04, RLC 1B-05 or 1B-06, MAC 1B-07 or 1B-08 and PHY 1B-09 or 1B-10.Control plane protocol stack consists of NAS 1B-11 or 1B-12, RRC 1B-13or 1B-14, PDCP, RLC, MAC and PHY.

Each protocol sublayer performs functions related to the operationslisted in the table 3.

TABLE 3 Sublayer Functions NAS authentication, mobility management,security control etc RRC System Information, Paging, Establishment,maintenance and release of an RRC connection, Security functions,Establishment, configuration, maintenance and release of SignallingRadio Bearers (SRBs) and Data Radio Bearers (DRBs), Mobility, QoSmanagement, Detection of and recovery from radio link failure, NASmessage transfer etc. SDAP Mapping between a QoS flow and a data radiobearer, Marking QoS flow ID (QFI) in both DL and UL packets. PDCPTransfer of data, Header compression and decompression, Ciphering anddeciphering, Integrity protection and integrity verification,Duplication, Reordering and in-order delivery, Out-of-order deliveryetc. RLC Transfer of upper layer PDUs, Error Correction through ARQ,Segmentation and re-segmentation of RLC SDUs, Reassembly of SDU, RLCre-establishment etc. MAC Mapping between logical channels and transportchannels, Multiplexing/demultiplexing of MAC SDUs belonging to one ordifferent logical channels into/from transport blocks (TB) deliveredto/from the physical layer on transport channels, Scheduling informationreporting, Priority handling between UEs, Priority handling betweenlogical channels of one UE etc. PHY Channel coding, Physical-layerhybrid-ARQ processing, Rate matching, Scrambling, Modulation, Layermapping, Downlink Control Information, Uplink Control Information etc.

A reduced capability UE or RedCap UE has lower performance than ageneral UE and is used in limited scenarios such as IOT. Compared to atypical terminal having a bandwidth of 100 MHz, a transmission/receptionspeed of several Gbps, and four or more Rx processing units (Rxbranches), RedCap terminals have a bandwidth of 20 MHz, atransmission/reception speed of several tens of Mbps, and two or less Rxprocessing units.

The present invention provides a method and apparatus for a RedCap UE toaccess a cell supporting RedCap, receive system information, and performnecessary operations. In particular, the terminal applies search space 0(Search Space 0, hereinafter SS #0) and control resource set 0 (ControlResource Set 0, hereinafter CORESET #0) in the initial bandwidth part(IBWP) to obtain system information.

FIG. 2A is a diagram illustrating an example of a bandwidth part.

With Bandwidth Adaptation (BA), the receive and transmit bandwidth of aUE need not be as large as the bandwidth of the cell and can beadjusted: the width can be ordered to change (e.g. to shrink duringperiod of low activity to save power); the location can move in thefrequency domain (e.g. to increase scheduling flexibility); and thesubcarrier spacing can be ordered to change (e.g. to allow differentservices). A subset of the total cell bandwidth of a cell is referred toas a Bandwidth Part (BWP) and BA is achieved by configuring the UE withBWP(s) and telling the UE which of the configured BWPs is currently theactive one.

FIG. 2A describes a scenario where 3 different BWPs are configured:

-   -   BWP1 with a width of 40 MHz and subcarrier spacing of 15 kHz;        2A-11 or 2A-19    -   BWP2 with a width of 10 MHz and subcarrier spacing of 15 kHz;        2A-13 or 2A-17    -   BWP3 with a width of 20 MHz and subcarrier spacing of 60 kHz.        2A-15

FIG. 2B is a diagram illustrating an example of a search space and acontrol resource set.

A plurality of SSs may be configured in one BWP. The UE monitors PDCCHcandidates according to the SS configuration of the currently activeBWP. One SS consists of an SS identifier, a CORESET identifierindicating the associated CORESET, the period and offset of the slot tobe monitored, the slot unit duration, the symbol to be monitored in theslot, the SS type, and the like. The information may be explicitly andindividually configured or may be configured by a predetermined indexrelated to predetermined values.

One CORESET consists of a CORESET identifier, frequency domain resourceinformation, symbol unit duration, TCI state information, and the like.

Basically, it can be understood that CORESET provides frequency domaininformation to be monitored by the UE, and SS provides time domaininformation to be monitored by the UE.

CORESET #0 and SS #0 may be configured in the IBWP. One CORESET and aplurality of SSs may be additionally configured in the IBWP. Uponreceiving the MIB 2B-01, the UE recognizes CORESET #0 2B-02 and SS #02B-03 for receiving SIB1 using predetermined information included in theMIB. The UE receives SIB1 2B-05 through CORESET #0 2B-02 and SS #02B-03. In SIB1, information constituting CORESET #0 2B-06 and SS #02B-07 and information constituting another CORESET, for example, CORESET#n 2B-11 and SS #m 2B-13 may be included.

The terminal receives necessary information from the base station beforethe terminal enters the RRC_CONNECTED state, such as SIB2 reception,paging reception, and random access response message reception by usingthe CORESETs and SSs configured in SIB1. CORESET #0 2B-02 configured inMIB and CORESET #0 2B-06 configured in SIB1 may be different from eachother, and the former is called a first CORESET #0 and the latter iscalled a second CORESET #0. SS #0 2B-03 configured in MIB and SS #02B-07 configured in SIB1 may be different from each other, and theformer is referred to as a first SS #0 and the latter is referred to asa second SS #0. SS #0 and CORESET #0 configured for the RedCap terminalare referred to as a third SS #0 and a third CORESET #0. The first SS#0, the second SS #0, and the third SS #0 may be the same as ordifferent from each other. The first CORESET #0, the second CORESET #0,and the third CORESET #0 may be the same as or different from eachother. SS #0 and CORESET #0 are each indicated by a 4-bit index. The4-bit index indicates a configuration predetermined in the standardspecification. Except for SS #0 and CORESET #0, the detailedconfiguration of the remaining SS and CORSESET is indicated by eachindividual information element.

When the RRC connection is established, additional BWPs may beconfigured for the UE.

FIG. 3 is a diagram illustrating operations of a terminal and a basestation according to an embodiment of the present disclosure.

In a network consisting of a RedCap UE 3A-01, a base station 3A-03 andan AMF 3A-05, the RedCap UE receives system information, determineswhether to bar a cell, performs cell reselection, monitors a pagingmessage, selects and applies cell common configuration information andtransmits and receives RRC control messages.

In step 3A-11, the RedCap UE camps on a cell managed by the base stationby performing cell selection or cell reselection. The RedCap UE selectsa cell having a good reception signal from among cells of the highestpriority frequency in consideration of cell reselection priority and thelike.

In step 3A-13, the RedCap UE receives the MIB in the selected cell.

The MIB includes controlResourceSetZero, which is a 4-bit indexindicating the configuration of the first CORESET #0, andcontrolResourceSetZero, which is a 4-bit index, indicating theconfiguration of the first SS #0. The UE receives SIB1 by applying thefrequency domain and time pattern indicated by the first CORESET #0 andthe first SS #0.

The MIB includes cellBarred, which is 1-bit information indicatingwhether or not the cell is barred. cellBarred indicates either barred ornotBarred. The UE uses cellBarred to determine whether to bar the cell.

The MIB includes a first intraFreqReselection that is 1-bit informationfor controlling intra-frequency cell reselection. The firstintraFreqReselection is defined as Enumerated {allowed, notAllowed}.Also called IFRI_MIB.

In steps 3A-15, the RedCap UE receives SIB1. The RedCap UE stores theacquired SIB1. SIB1 includes ServingCellConfigCommon, which is commonconfiguration information of a serving cell, and a secondintraFreqReselection. The second intraFreqReselection is defined asenumerated with one of Allowed and notAllowed. It is also calledIFRI_SIB.

In step 3A-16, the RedCap UE selects one of a plurality of commonconfiguration information included in ServingCellConfigCommon.

The servingCellConfigCommon of SIB1 includes the following information.

TABLE 4 DownlinkConfigCommon This is a common downlink configuration ofthe serving cell. It consists of subfields such as frequencyInfoDL,initialDownlinkBWP, bcch- Config, and pcch-Config. frequencyInfoDL It isa basic parameter of a downlink carrier. It consists of subfields suchas a frequency band list and carrier bandwidth for each SCS.initialDownlinkBWP This is the configuration of the second downlinkIBWP. It consists of subfields such as BWP, PDCCH- ConfigCommon, andPDSCH-ConfigCommon. The first IBWP has a frequency domain correspondingto the first CORESET#0 of the MIB and has subcarrier spacing indicatedby the MIB. The first IBWP is the IBWP indicated by the MIB and used forreceiving SIB1, the second IBWP is the IBWP indicated by the SIB1 andused for receiving the SIB2, paging, random access response message, andthe like. BWP It is IE that configures general parameters of BWP. Itconsists of subfields such as locationAndBandwidth indicating thebandwidth and location of the BWP, and subcarrierSpacing indicating theSCS of the BWP. PDCCH-ConfigCommon It is the cell-specific PDCCHparameters of the BWP. It consists of subfields such ascontrolResourceSetZero, commonControlResourceSet, searchSpaceZero,commonSearchSpaceList, searchSpaceOtherSystemInformation,pagingSearchSpace, and ra-SearchSpace. controlResourceSetZero It isdefined as an integer between 0 and 15. Indicates one of the predefinedCORESET#0 configurations. The controlResourceSetZero included in the MIBcorresponds to the first CORESET#0, and the controlResourceSetZeroincluded in the PDCCH- ConfigCommon of the servingCellConfigCommon ofSIB1 corresponds to the second CORESET#0. searchSpaceZero It is definedas an integer between 0 and 15. Indicates one of the predefined SS#0configurations. The searchSpaceZero included in the MIB corresponds tothe first SS#0, and the controlResourceSetZero included in thePDCCH-ConfigCommon of the servingCellConfigCommon of SIB1 corresponds tothe second SS#0. commonControlResourceSet A common CORESET defined byControlResourceSet IE. Defines an additional CORESET that can be usedfor paging reception, random access response reception, systeminformation reception, etc. commonSearchSpaceList List of common SSs.The common SS may be used for paging reception, random access responsereception, system information reception, and the like.searchSpaceOtherSystemInformation Defined by the SS identifier IE. If itis 0, the second SS#0 is indicated, and if it is a value other than 0,one of the SSs defined in commonSearchSpaceList is indicated.pagingSearchSpace Defined by the SS identifier IE. If it is 0, thesecond SS#0 is indicated, and if it is a value other than 0, one of theSSs defined in commonSearchSpaceList is indicated. ra-SearchSpaceDefined by the SS identifier IE. If it is 0, the second SS#0 isindicated. If it is a value other than 0, one of the SSs defined in thecommonSearchSpaceList is indicated. PDSCH-ConfigCommon Cell-specificPDSCH parameters of this BWP. It consists of apdsch-TimeDomainAllocationList. The pdsch-TimeDomainAllocationList is alist composed of a plurality of pdsch-TimeDomainAllocations.pdsch-TimeDomainAllocation A time domain relationship between the PDCCHand the PDSCH. It consists of subfields such as K0 andstartSymbolAndLength. K0 is the slot offset between the DCI and thescheduled PDSCH. startSymbolAndLength is an index indicating a validstart symbol and length combination. pcch-Config Configuration relatedto paging. It consists of sub- fields such as the base station pagingperiod, PF- related parameters, and PO-related parameters. bcch-configIt is a configuration related to system information. It consists ofsubfields such as modificationPeriodCoeff indicating the length of themodification period. UplinkConfigCommonSIB This is a common uplinkconfiguration of the serving cell. It consists of subfields such asfrequencylnfoUL, initialUplinkBWP, and timeAlignmentTimerCommon.frequencyInfoUL It is a basic parameter of the uplink carrier. Itconsists of subfields such as a frequency band list and carrierbandwidth for each SCS. initialUplinkBWP This is the configuration ofthe second uplink IBWP. It consists of subfields such as BWP, rach-ConfigCommon, pusch-ConfigCommon, and pucch- ConfigCommon.rach-ConfigCommon This is the cell-specific random access parameter ofthe BWP. It consists of subfields such as prach- ConfigurationIndex,msg1-FrequencyStart, preambleReceivedTargetPower, ra- ResponseWindow,preambleTransMax, msg1- SubcarrierSpacing, rsrp-ThresholdSSB, and ra-ContentionResolutionTimer. prach-ConfigurationIndex PRACH configurationindex. One PRACH configuration corresponds to pattern information on aPRACH transmission opportunity in the time domain (informationindicating in which symbol in which slot of which radio frame PRACHtransmission is possible), a transmission format of a preamble, and thelike. msg1-FrequencyStart The offset from PRB0 of the lowest PRACHtransmission opportunity. Information indicating a PRACH transmissionresource in the frequency domain. PRB0 is the lowest frequency PRB amongPRBs of the corresponding carrier. preambleReceivedTargetPower This isthe target power level of the network receiving end. It is a parameterrelated to transmission power control during the random accessprocedure. ra-ResponseWindow The length of the random access responsewindow expressed in the number of slots. preambleTransMax The maximumnumber of random access preamble transmissions msg1-SubcarrierSpacing Itis PRACH's SCS. It is commonly applied to general terminals and RedCapUEs. rsrp-ThresholdSSB SSB selection criteria. The UE performs randomaccess by selecting a preamble corresponding to the selected SSB.ra-ContentionResolutionTimer This is the initial value of the contentionresolution timer. Indicates the number of subframes. pusch-ConfigCommonCell-specific PUSCH parameters of this BWP. It consists of subfieldslike pusch- TimeDomainAllocationList. The pusch-TimeDomainAllocationList is a list composed of a plurality ofpusch-TimeDomainAllocations. pusch-TimeDomainAllocation A time domainrelationship between the PDCCH and the PUSCH. It consists of subfieldssuch as K2 and startSymbolAndLength. K2 is the slot offset between theDCI and the scheduled PUSCH. startSymbolAndLength is an index indicatinga valid combination of start symbol and length. pucch-ConfigCommon Thisis the cell-specific PUCCH parameter of the BWP. It consists ofsubfields such as pucch- ResourceCommon and p0-norminal.pucch-ResourceCommon It is an index corresponding to a cell-specificPUCCH resource parameters. One index corresponds to a PUCCH format, aPUCCH time period, a PUCCH frequency period, a PUCCH code, and the like.p0-norminal This is a power offset applied during PUCCH transmission.Defined as an integer between -202 and 24 in increments of 2. The unitis dBm. timeAlignmentTimerCommon This is a timer applied when the UEperforms random access for RRC connection establishment procedure andRRC connection re-establishment procedure. When the UE receives the RAR,it starts the timer, and stops the timer when contention fails.tdd-UL-DL-ConfigurationCommon Cell specific TDD UL/DL configuration. Itconsists of subfields such as referenceSubcarrierSpacing, pattern1, andpattern2. referenceSubcarrierSpacing This is the reference SCS used todetermine the time domain boundary in the UL-DL pattern. pattern1,pattern2 TDD Uplink Downlink Pattern. It consists of subfields such asdl-UL-TransmissionPeriodicity, nrofDownlinkSlots, nrofDownlinkSymbols,nrofUplinkSlots, and nrofUplinkSymbols. dl-UL-TransmissionPeriodicityIndicates the period of the DL-UL pattern. nrofDownlinkSlots Indicatesthe number of consecutive full DL slots in each DL-UL pattern.nrofDownlinkSymbols Indicates the number of consecutive DL symbols fromthe beginning of the slot following the last full DL slot.nrofUplinkSlots Indicates the number of consecutive full UL slots ineach DL-UL pattern. nrofUplinkSymbols Indicates the number ofconsecutive UL symbols at the last time point of a slot preceding thefirst full UL slotServingCellConfigCommon may also include the following information forRedCap UE.

TABLE 5 controlResourceSetZero_RedCap It is defined as an integerbetween 0 and 15. Indicates one of the predefined CORESET#0configurations. It corresponds to the third CORESET #0.searchSpaceZero_RedCap It is defined as an integer between 0 and 15.Indicates one of the predefined SS#0 configurations. It corresponds tothe third SS#0. searchSpaceOtherSystemInformation_RedCap Defined by theSS identifier IE. If it is 0, the third SS#0 is indicateed, if not 0,one of the SSs defined in commonSearchSpaceList is indicateed.ra-SearchSpace_RedCap Defined by the SS identifier IE. If it is 0, thethird SS#0 is indicateed, if not 0, one of the SSs defined incommonSearchSpaceList is indicateed. . prach-ConfigurationIndex_RedCapPRACH configuration index for RedCap. msg1-FrequencyStart_RedCap PRACHtransmission resource information on the frequency domain for RedCappreambleReceivedTargetPower_RedCap The target power level of the networkreceiver for RedCap. ra-ResponseWindow_RedCap Length of the randomaccess response window for RedCap. preambleTransMax_RedCap Maximumnumber of random access preamble transmissions for RedCaprsrp-ThresholdSSB_RedCap SSB selection criteria for RedCap. ra- Initialvalue of the contention resolution timer forContentionResolutionTimer_RedCap RedCap. intraFreqReselection_RedCapControls cell selection/reselection within the frequency of RedCap UEwhen the highest-priority cell is barred. It is 1-bit information and isdefined as Enumerated {Allowed, notAllowed}. Also called IFRI_SIB1.

IFRI_MIB is defined to be present mandatorily and IFRI_SIB1 is definedto be present optionally. This is to ensure backward compatibility ofSIB1.

Instead of defining IEs for RedCap UEs in units of individual IEs, it isalso possible to define configuration information related to RedCap UEsin units of IE sets as follows.

ServingCellConfigCommon of SIB1 includes downlink IBWP configurationinformation and uplink IBWP configuration information.

Downlink IBWP configuration information includes PDCCH-ConfigCommon andPDCCH-ConfigCommon2. PDCCH-ConfigCommon is used by general terminals andRedCap UEs, and PDCCH-ConfigCommon2 is used by RedCap UEs. RedCap UEuses PDCCH-ConfigCommon when only PDCCH-ConfigCommon is included indownlink IBWP configuration information and uses PDCCH-ConfigCommon2when both PDCCH-ConfigCommon and PDCCH-ConfigCommon2 are included.

PDCCH-ConfigCommon includes controlResourceSetZero,commonControlResourceSet, searchSpaceZero, commonSearchSpaceList,searchSpaceOtherSystemInformation, pagingSearchSpace, andra-SearchSpace. PDCCH-ConfigCommon2 includescontrolResourceSetZero_RedCap, commonControlResourceSet_RedCap,searchSpaceZero_RedCap, commonSearchSpaceList_RedCap,ra-SearchSpace_RedCap.

RedCap UE uses controlResourceSetZero and searchSpaceZero ofPDCCH-ConfigCommon if controlResourceSetZero_RedCap andsearchSpaceZero_RedCap are not included in PDCCH-ConfigCommon2. That is,it is considered that the same value as the second SS #0 is configuredfor the third SS #0 and the same value as the second CORESET #0 isconfigured for the third CORESET #0.

The RedCap UE uses the values indicated in the MIB whencontrolResourceSetZero_RedCap and searchSpaceZero_RedCap are notincluded in PDCCH-ConfigCommon2 and controlResourceSetZero andsearchSpaceZero are not included in PDCCH-ConfigCommon. That is, it isconsidered that the same value as the first SS #0 is configured for thethird SS #0 and the same value as the first CORESET #0 is configured forthe third CORESET #0.

RedCap UE uses ra-SearchSpace of PDCCH-ConfigCommon ifra-SearchSpace_RedCap is not included in PDCCH-ConfigCommon2. That is,it is considered that the same value as ra-SearchSpace is set asra-SearchSpace_RedCap. The RedCap UE performs a random access procedureby applying the third SS #0 and the third CORESET #0.

The uplink IBWP configuration information includes PUCCH-ConfigCommonand PUCCH-ConfigCommon2. PUCCH-ConfigCommon is used by general UEs andRedCap UEs, and PUCCH-ConfigCommon2 is used by RedCap UEs. RedCap UEuses PUCCH-ConfigCommon when only PUCCH-ConfigCommon is included inuplink IBWP configuration information, and uses PUCCH-ConfigCommon2 whenboth PUCCH-ConfigCommon and PUCCH-ConfigCommon2 are included.

PUCCH-ConfigCommon2 is used by RedCap UE. PUCCH-ConfigCommon containspusch-TimeDomainAllocationList. PUCCH-ConfigCommon2 containspusch-TimeDomainAllocationList_RedCap.

The uplink IBWP configuration information includes RACH-ConfigCommon andRACH-ConfigCommon2. RACH-ConfigCommon is used by general terminals andRedCap UEs, and RACH-ConfigCommon2 are used by RedCap UEs. RedCap UEuses RACH-ConfigCommon when only RACH-ConfigCommon is included in uplinkIBWP configuration information, and uses RACH-ConfigCommon2 when bothRACH-ConfigCommon and RACH-ConfigCommon2 are included.

RACH-ConfigCommon includes prach-ConfigurationIndex,msg1-FrequencyStart, preambleReceivedTargetPower, ra-ResponseWindow,preambleTransMax, msg1-SubcarrierSpacing, rsrp-ThresholdSSB, andra-ContentionResolutionTimer.

RACH-ConfigCommon2 includes prach-ConfigurationIndex_RedCap,msg1-FrequencyStart_RedCap, preambleReceivedTargetPower_RedCap,ra-ResponseWindow_RedCap, preambleTransMax_RedCap,rsrp-ThresholdSSB_RedCap, ra-ContentionResolutionTimer_RedCap.msg1-SubcarrierSpacing included in RACH-ConfigCommon is applied to bothnormal UEs and RedCap UEs. In other words, the RedCap UE appliesmsg1-FrequencyStart included in RACH-ConfigCommon2 andmsg1-SubcarrierSpacing included in RACH-ConfigCommon when applying msg1frequency-related information.

If RACH-ConfigCommon2 does not contain prach-ConfigurationIndex_RedCap,msg1-FrequencyStart_RedCap, preambleReceivedTargetPower_RedCap,ra-ResponseWindow_RedCap, preambleTransMax_RedCap,msg1-SubcarrierSpacing_RedCap, rsrp-ThresholdSSB_RedCap,ra-ContentionResolutionTimer_RedCap, RedCap UE uses a same values ofprach-ConfigurationIndex, a same values of msg1-FrequencyStart, a samevalues of preambleReceivedTargetPower, a same values ofra-ResponseWindow, a same values of preambleTransMax, a same values ofmsg1-SubcarrierSpacing, a same values of rsrp-ThresholdSSB, a samevalues of ra-ContentionResolutionTimer in RACH-ConfigCommonrespectively.

In another method, the ServingCellConfigCommon of SIB1 includes thefirst downlink IBWP configuration information, the first uplink IBWPconfiguration information, the second downlink IBWP configurationinformation, the second uplink IBWP configuration information, andtdd-UL-DL-ConfigurationCommon. The first downlink IBWP configurationinformation and the first uplink IBWP configuration information areinformation for a terminal with general capability, and the seconddownlink IBWP configuration information and the second uplink IBWPconfiguration information are information for a RedCap UE.tdd-UL-DL-ConfigurationCommon is information that is commonly applied toa UE with general capability and a RedCap UE.

The first uplink IBWP configuration information includespucch-ConfigCommon and timeAlignmentTimerCommon. The second uplink IBWPconfiguration information may include pucch-ConfigCommon_RedCap. Thepucch-ConfigCommon may include a first pucch-ResourceCommon and a firstp0-norminal. The pucch-ConfigCommon_RedCap may include a secondpucch-ResourceCommon and a second p0-norminal. pucch-ConfigCommon isinformation for a normal UE. pucch-ConfigCommon_RedCap is informationfor RedCap UE. timeAlignmentTimerCommon is information commonly appliedto normal UE and RedCap UE.

The RedCap UE transmits the preamble and initiatestimeAlignmentTimerCommon upon reception of the RAR. Upon receiving Msg4, the UE transmits a HARQ ACK by applying a predeterminedpucch-ResourceCommon and a predetermined p0-normal.

If both the second pucch-ResourceCommon and the firstpucch-ResourceCommon exist, the time/frequency/code resource fortransmitting the HARQ ACK is determined by applying the secondpucch-ResourceCommon. If only the first pucch-ResourceCommon exists, thetime/frequency/code resource for transmitting the HARQ ACK is determinedby applying the first pucch-ResourceCommon.

When both the second p0-norminal and the first p0-norminal exist, thesecond p0-norminal is applied to determine a power offset to be appliedto the HARQ ACK. If only the first p0-norminal exists, the power offsetto be applied to the HARQ ACK is determined by applying the firstp0-norminal. If neither the second p0-norminal nor the p0-norminalexist, a power offset to be applied to the HARQ ACK is determined byapplying a predetermined value. The predetermined value may be, forexample, 2 dBm.

In step 3A-17, the RedCap UE determines whether the current cell is abarred cell or an allowed cell, in consideration of MIB and SIB1.

Regarding cell barring, the RedCap UE determines that the current cellis not barred if all of the following conditions are satisfied. Theconditions below are defined so that the RedCap UE camps on the cellonly when it can operate properly in the cell.

<Cell Allowance Conditions>

0: The received MIB's cellBarred is set to notBarred.

1: IFRI_SIB1 exists (or is included) in the received SIB1. This isbecause the absence of IFRI_SIB1 means that the corresponding cell doesnot consider the operation of the RedCap UE, and the presence ofIFRI_SIB1 means that the corresponding cell is a cell that considers theoperation of the RedCap UE.

2: If the current cell is TDD cell, the UE supports one or more of thefrequency bands indicated in the frequencyBandList for downlink in thereceived SIB1 for TDD, or one or more of the frequency bands indicatedin the frequencyBandList for uplink in the received SIB1 for FDD, andthey are not downlink only bands, and

3: The UE supports an uplink channel bandwidth with a maximumtransmission bandwidth configuration fulfilling following conditions: Itis smaller than or equal to the uplink carrierBandwidth indicated inSIB1 and it is wider than or equal to the bandwidth of the initialuplink BWP

4: the UE supports a downlink channel bandwidth with a maximumtransmission bandwidth configuration fulfilling following conditions: Itis smaller than or equal to the downlink carrierBandwidth indicated inSIB1 it is wider than or equal to the bandwidth of the initial downlinkBWP

5: trackingAreaCode is provided in SIB1 for the selected PLMN or theregistered PLMN or PLMN of the equivalent PLMN list

For example, if trackingAreaCode x is included in SIB1 andtrackingAreaCode related to the registered PLMN of the terminal is alsox, condition 5 is satisfied. The trackingAreaCode related to the PLMN isprovided to the terminal by the AMF during the registration procedurewith the terminal.

The RedCap UE, which determines that the current cell is not barred,performs the following operation.

<Operation of Terminal after Receiving SIB1 in Non-Prohibited Cell>

1: Apply the configuration included in the servingCellConfigCommon. Morespecifically, the UE applies the TDD-UL-DL configuration to determine adownlink slot, an uplink slot, a downlink symbol, and an uplink symbol,and applies a PDSCH configuration selected from among a plurality ofPDSCH-ConfigCommon to receive a PDSCH, and applies a PUSCH configurationselected from among a plurality of PUSCH-ConfigCommon to transmit aPUSCH.

2: A specified PCCH configuration is applied. The specified PCCHconfiguration is no SDAP, no PDCP, and RLC TM. A paging message isreceived by applying the PCCH configuration.

3: If a valid SIB is stored, the stored SIB is used, and if a valid SIBis not stored, a related system information message (SI message) isacquired

The UE also receives subsequent system information, for example, SIB2,SIB3, SIB4, etc. in the not barred cell. SIB2 includes parameters forintra-frequency cell reselection. SIB3 includes other parameters forintra-frequency cell reselection. SIB4 contains parameters for cellreselection between frequencies.

The RedCap UE regards the current serving cell as a barred cell in thecases listed in the table below and performs an appropriate operationaccording to the situation.

TABLE 6 Case Situation RedCap UE operation 1 MIB reception failure Thecurrent cell is considered as a barred cell. The current cell isexcluded from cell selection/cell reselection candidates for 300seconds. It is assumed that both IFRI_MIB and IFRI_SIB1 are allowed.That is, neighboring cells of the corresponding frequency may beincluded in the cell selection/cell reselection candidates. 2 Successfulreception of The current cell is considered as a barred cell. MIB withcellBarred set to Excludes the current cell from candidates fornotBarred. cell selection/cell reselection for 300 seconds. SIB1reception failure If the received IFRI_MIB is allowed, IFRI_SIB1 isconsidered as allowed, and neighboring cells of the correspondingfrequency may be included in the cell selection/cell reselectioncandidates. If the received IFRI_MIB is NotAllowed, IFRI_SIB1 is alsoconsidered as NotAllowed, and neighboring cells of the correspondingfrequency are excluded from cell selection/cell reselection candidates.3 Successful reception of The current cell is considered a barred cell.MIB with cellBarred set to Excludes the current cell from candidates forBarred. cell selection/cell reselection for 300 seconds. If the receivedIFRI_MIB is allowed, IFRI_SIB1 is considered as allowed, and neighboringcells of the corresponding frequency may be included in the cellselection/cell reselection candidates. If the received IFRI_MIB isNotAllowed, IFRI_SIB1 is also considered as NotAllowed, and neighboringcells of the corresponding frequency are excluded from the cellselection/cell reselection candidates. The general terminal does notreceive SIB1. The RedCap UE may receive SIB1 instead of referring toIFRI_MIB, and may exclude or include neighboring cells of thecorresponding frequency from cell selection/cell reselection candidatesaccording to the received value of IFRI_SIB1. 4 Successful MIB receptionThe current cell is considered as a barred cell. with cellBarred set toExcludes the current cell from candidates for notBarred. SIB1 receptioncell selection/cell reselection for 300 seconds. without IFRI_SIB1Regardless of the value of the received IFRI_MIB, IFRI_SIB1 may beconsidered as NotAllowed and neighboring cells of the correspondingfrequency may be excluded from cell selection/cell reselectioncandidates. 5 Successfully received MIB The current cell is considered abarred cell. with cellBarred set to Excludes the current cell fromcandidates for notBarred. Received SIB1 cell selection/cell reselectionfor 300 seconds. with IFRI_SIB1 According to the received IFRI_SIBvalue, The bandwidth supported neighboring cells of the corresponding bythe terminal is less than frequency are included or excluded from thecell the bandwidth of the IBWP. selection/cell reselection candidates. 6Successful reception of The current cell is considered a barred cell.MIB with cellBarred set to Excludes the current cell from candidates fornotBarred. Received SIB1 cell selection/cell reselection for 300seconds. with IFRI_SIB1 Regardless of the received IFRI values, both Thebandwidth supported IFRI_MIB and IFRI_SIB1 are considered as by theterminal is greater NotAllowed and neighboring cells of the than orequal to the corresponding frequency are excluded from cell bandwidth ofthe IBWP. selection/cell reselection candidates. There is noTrackingAreaCode matching the TrackingAreaCode received from SIB1.

The reason why the RedCap UE operates as described above is to preventcamp-on in a cell that does not support the RedCap function and toappropriately control whether or not to reselect cells for cells of thesame frequency. If there is no IFRI to be referred to as in case 1, bothIFRIs may be assumed to be a predetermined value and may be operatedaccordingly. Alternatively, if reception of IFRI_SIB1 fails as in case2, IFRI_MIB may be referred to.

The RedCap UE may be given two IFRI parameters: IFRI_MIB and IFRI_SIB1.RedCap UE considers two parameters and determines whether to allowintra-frequency reselection as shown in the table below.

TABLE 7 IFRI_MIB IFRI_SIB1 RedCap UE operation Note Reception ReceptionIFRI_SIB1 is considered as failure failure Allowed Allowed ReceptionIFRI_SIB1 is considered as IFRI_SIB1 considered as the failure Allowedsame value as IFRI_MIB Allowed Not IFRI_SIB1 is considered as It isdetermined that RedCap Present NotAllowed is not supported in thecorresponding frequency. Allowed Allowed IFRI_SIB1 is considered as thereceived IFRI_SIB1 is Allowed applied as it is Allowed NotAllowedIFRI_SIB1 is considered as the received IFRI_SIB1 is NotAllowed appliedas it is NotAllowed Reception IFRI_SIB1 is considered as IFRI_SIB1considered as the failure NotAllowed same value as IFRI_MIB NotAllowedNot IFRI_SIB1 is considered as It is determined that RedCap PresentNotAllowed is not supported in the corresponding frequency. NotAllowedAllowed IFRI_SIB1 is considered as the received IFRI_SIB1 is Allowedapplied as it is NotAllowed NotAllowed IFRI_SIB1 is considered as thereceived IFRI_SIB1 is NotAllowed applied as it is

The RedCap UE applies the received IFRI_SIB1, if both IFRI_MIB andIFRI_SIB1 are received.

The RedCap UE considers that IFRI_SIB1 is Allowed If neither IFRI_MIBnor IFRI_SIB1 are received.

If the RedCap UE receives IFRI_MIB but does not receive IFRI_SIB1, itdetermines IFRI_SIB1 by distinguishing whether SIB1 reception has failedor IFRI_SIB1 is not included in SIB1. If the reception of SIB1 isunsuccessful, the UE considers that IFRI_SIB1 is the same as IFRI_MIB.If SIB1 is received but IFRI_SIB1 is not included, the UE considers thatIFRI_SIB1 is a predetermined value (eg, notAllowed). This is because,since cells of the same frequency in the same region are highly likelyto be configured identically, if IFRI_SIB1 is not provided in thecurrent cell, it is highly likely that IFRI_SIB1 is not provided inother cells as well. Alternatively, If IFRI_SIB1 is preconfigured to beconsidered as Allowed when UE has received SIB1 from the base stationbut IFRI_SIB1 is not included, IFRI_SIB1 is considered as Allowed.

If MIB reception fails, IFRI_MIB cannot be received.

If IFRI_SIB1 is Allowed, the RedCap UE may select or reselect othercells of the same frequency as the barred cell if the cell reselectionselection criteria are fulfilled

If IFRI_SIB1 is NotAllowed, for 300 seconds the RedCap UE does notselect or reselect other cells of the same frequency as the barred cell,and excludes them from candidates for cell selection/reselection.

If IFRI_SIB1 is NotAllowed, the RedCap UE sets the cell reselectionpriority of the frequency of the barred cell for 300 seconds to thelowest priority. The RedCap UE performs cell reselection for frequenciesother than the barred cell frequency. At this time, the RedCap UEperforms cell reselection by applying the cell reselection priorityindicated in the system information received from an NR cell other thanthe first NR cell.

A UE camped on a not barred cell and prepares to perform random accessin order to perform a necessary procedure. The UE refers to the receivedServingCellConfigCommon.

In steps 3A-21, the RedCap UE transmits a preamble to the base station.

If both prach-ConfigurationIndex_RedCap and prach-ConfigurationIndex areincluded in rach-ConfigCommon (or ServingCellConfigCommon), the RedCapUE applies prach-ConfigurationIndex_RedCap to determine a radio frame,subframe, slot, symbol and preamble format in which preambletransmission is possible. If only prach-ConfigurationIndex is includedin rach-ConfigCommon (or in ServingCellConfigCommon), RedCap UEdetermines radio frame, subframe, slot, symbol and preamble format inwhich preamble transmission is possible by applyingprach-ConfigurationIndex.

If both msg1-FrequencyStart_RedCap and msg1-FrequencyStart are includedin rach-ConfigCommon (or ServingCellConfigCommon), the RedCap UE appliesmsg1-FrequencyStart_RedCap to determine a frequency region in whichpreamble transmission is possible. If only msg1-FrequencyStart isincluded in rach-ConfigCommon (or ServingCellConfigCommon), RedCap UEapplies msg1-FrequencyStart to determine a frequency range in whichpreamble transmission is possible.

RedCap UE selects SSB by applying rsrp-ThresholdSSB_RedCap if bothrsrp-ThresholdSSB_RedCap and rsrp-ThresholdSSB are included inrach-ConfigCommon (or in ServingCellConfigCommon). RedCap UE selects SSBby applying rsrp-ThresholdSSB if only rsrp-ThresholdSSB is included inrach-ConfigCommon (or ServingCellConfigCommon). The terminal selects anSSB having the highest received signal strength among SSBs having areceived signal strength higher than the threshold value. The UE selectsa preamble/PRACH transmission opportunity (Occasion) corresponding tothe selected SSB and transmits the preamble.

After transmitting the preamble, the UE monitors whether a random accessresponse message is received during the random access response window,and if not received, retransmits the preamble. As the maximum number ofpreamble retransmissions, the UE applies preambleTransMax_RedCap whenboth preambleTransMax_RedCap and preambleTransMax are included inServingCellConfigCommon, and applies preambleTransMax when onlypreambleTransMax is included. The UE applies msg1-SubcarrierSpacingincluded in rach-ConfigCommon when transmitting the preamble.

One ServingCellConfigCommon may include two prach-ConfigurationIndex,two msg1-FrequencyStart, two rsrp-ThresholdSSB, two preambleTransMax andone msg1-SubcarrierSpacing for Msg1 transmission. One of the twoprach-ConfigurationIndex, one of the two msg1-FrequencyStart, one of thetwo rsrp-ThresholdSSB, and one of the two preambleTransMax apply only toRedCap UEs, and msg1-SubcarrierSpacing is applied to both RedCap UEs andnon-RedCap UEs. Msg 1 is the preamble.

In steps 3A-23, a random access response message is received from thebase station. The random access response message includes informationsuch as an uplink grant for Msg 3 transmission, a time domain allocationindicator, and a temporary identifier of the terminal.

The random access response message is addressed by the RA-RNTI. Theterminal receives a random access response message by monitoring apredetermined SS in a predetermined CORESET in the random access windowtime period.

If ServingCellConfigCommon includes controlResourceSetZero,searchSpaceZero, ra-SearchSpace, controlResourceSetZero_RedCap,searchSpaceZero_RedCap, and ra-SearchSpace_RedCap and Ifra-SearchSpace_RedCap indicates 0, RedCap UE applies 3rd CORESET #0 and3rd SS #0 to RA-Monitor the RNTI and receive a random access responsemessage.

If only controlResourceSetZero, searchSpaceZero, and ra-SearchSpace areincluded in servingCellConfigCommon and If ra-SearchSpace indicates 0,the RedCap UE applies the 2nd CORESET #0 and the 2nd SS #0 to monitorthe RA-RNTI and receive a random access response message.

If controlResourceSetZero, searchSpaceZero, ra-SearchSpace,controlResourceSetZero_RedCap, searchSpaceZero_RedCap, andra-SearchSpace_RedCap are all included in servingCellConfigCommon and ifra-SearchSpace_RedCap indicates a value other than 0, the RedCap UEapplies the SS having the indicated identifier and the CORESETassociated with the SS to monitor RA-RNTI and receive a random accessresponse message.

If only controlResourceSetZero, searchSpaceZero and ra-SearchSpace areincluded in servingCellConfigCommon and if ra-SearchSpace indicates avalue other than 0, the RedCap UE applies the SS having the indicatedidentifier and the CORESET associated with the SS to monitor RA-RNTI andreceive a random access response message.

If both ra-ResponseWindow and ra-ResponseWindow_RedCap are included inServingCellConfigCommon, the RedCap UE determines the length of therandom access response window by applying ra-ResponseWindow_RedCap.

If only ra-ResponseWindow is included in ServingCellConfigCommon, RedCapUE determines the length of the random access response window byapplying ra-ResponseWindow.

Upon receiving the random access response, the RedCap UE startstlmeAlignmentTimer and generates a MAC PDU to transmit Msg 3 to the basestation. The MAC PDU includes an uplink RRC control message such asRRCRequest.

In step 3A-25, the RedCap UE transmits Msg 3 to the base station andstarts the contention resolution timer. If servingCellConfigCommoncontains both ra-ConttentionResolutionTimer andra-ContentionResolutionTimer_RedCap, the RedCap UE sets the contentionresolution timer to ra-ContentionResolutionTimer_RedCap. IfservingCellConfigCommon contains only ra-ConttentionResolutionTimer,RedCap UE sets contention resolution timer to ContentionResolutionTimer.

Msg 3 transmission time is determined by the time domain allocationindicator of the random access response message. The RedCap UEdetermines the start time and transmission duration of the PUSCH towhich Msg 3 is to be transmitted according to the PUSCH time domainallocation entry, indicated by a time domain allocation indicator, of aspecific list from among a pusch-TimeDomainAllocationList, a secondpusch-5 TimeDomainAllocationList and a default list.

In steps 3A-27, the RedCap UE receives Msg 4 from the base station. Msg4 includes a downlink RRC control message such as RRCSetup.

The RedCap UE determines a transmission resource for transmitting theHARQ ACK for Msg 4 by selecting one of the first PUCCH common resourceinformation (pucch-ResourceCommon) and the second PUCCH common resourceinformation (pucch-ResourceCommon).

The RedCap UE determines the nominal power offset to be applied to HARQACK transmission for Msg 4 by selecting one of a nominal power offset(p0-normal) included in the first PUCCH common configuration information(pucch-ConfigCommon) and a nominal power offset (p0-norminal) includedin the second PUCCH common configuration information(pucch-ConfigCommon) and a nominal power offset fixed to a predeterminedvalue.

The RedCap UE and the base station that have transmitted and receivedthe RRCRequest message and the RRCSetup message establish an RRCconnection.

The base station and the AMF may transmit/receive various NAS messagesand control messages to the UE for which the RRC connection isconfigured in steps 3A-31.

The RedCap UE and the base station can exchange configurationinformation and the like through RRC connection, configure a bearer, andthen transmit/receive data.

In ServingCellConfigCommon of SIB1, PDCCH-ConfigCommon2 is locatedbehind PDCCH-ConfigCommon. In ServingCellConfigCommon of SIB1,PUCCH-ConfigCommon2 is located behind PUCCH-ConfigCommon. InServingCellConfigCommon of SIB1, RACH-ConfigCommon2 is located behindRACH-ConfigCommon.

In ServingCellConfigCommon of SIB1, the second downlink IBWPconfiguration information is located behind the first downlink IBWPconfiguration information. In ServingCellConfigCommon of SIB1, thesecond uplink IBWP configuration information is located behind the firstuplink IBWP configuration information. In ServingCellConfigCommon ofSIB1, controlResourceSetZero_RedCap is located behindcontrolResourceSetZero. In ServingCellConfigCommon of SIB1,searchSpaceZero_RedCap is located behind searchSpaceZero. InServingCellConfigCommon of SIB1, ra-SearchSpace_RedCap is located behindra-SearchSpace. The order of various pieces of information is defined asdescribed above in order to maintain backward compatibility with aterminal or a base station of a previous release.

FIG. 4 is a diagram illustrating an operation of a terminal.

In step 4A-01, the reduced capability terminal receives in the first NRcell a master information block with a first information indicatingwhether or not the cell is barred set to notBarred including a firstintra-frequency cell reselection information element for controllingintra-frequency cell reselection and a second information elementcorresponding to time/frequency where system information block 1 isscheduled.

In step 4A-03, the reduced capability terminal receives the systeminformation block 1 using the second information element.

In step 4A-05, the reduced capability terminal determines the secondIFRI and whether the first NR cell is barred.

In step 4A-07, the reduced capability terminal performs cell selectionor reselection according to the determination.

If the reduced capability terminal does not receive SIB1 in the first NRcell, reduced capability terminal determines that the first NR cell is abarred cell, excludes the first NR cell from the candidates for cellselection and cell reselection for 300 seconds, consider the second IFRIis identical to the first IFRI and determined whether to include orexclude the second NR cell of the same frequency as the first NR cell asa candidate for cell selection/re selection.

If the SIB1 received in the first NR cell does not include the secondIFRI, reduced capability terminal determines that the first NR cell is abarred cell, excludes the first NR cell from the candidates for cellselection and cell reselection for 300 seconds, consider the second IFRIis set to notAllowed and determined to exclude the second NR cell of thesame frequency as the first NR cell as a candidate for cellselection/reselection.

In order to ensure backward compatibility with the previous release basestation or terminal, the first IFRI IE is defined as a mandatoryexistence indicating one of Allowed and notAllowed, and the second IFRIIE is defined as an optional existence indicating one of Allowed andnotAllowed. FIG. 5A is a block diagram illustrating the internalstructure of a UE to which the disclosure is applied.

Referring to the diagram, the UE includes a controller 5A-01, a storageunit 5A-02, a transceiver 5A-03, a main processor 5A-04 and I/O unit5A-05.

The controller 5A-01 controls the overall operations of the UE in termsof mobile communication. For example, the controller 5A-01receives/transmits signals through the transceiver 5A-03. In addition,the controller 5A-01 writes and reads data in the storage unit 5A-02. Tothis end, the controller 5A-01 includes at least one processor. Forexample, the controller 5A-01 may include a communication processor (CP)that performs control for communication and an application processor(AP) that controls the upper layer, such as an application program. Thecontroller controls storage unit and transceiver such that UE operationsillustrated in FIG. 3 and FIG. 4 are performed.

The storage unit 5A-02 stores data for operation of the UE, such as abasic program, an application program, and configuration information.The storage unit 5A-02 provides stored data at a request of thecontroller 5A-01.

The transceiver 5A-03 consists of a RF processor, a baseband processorand plurality of antennas. The RF processor performs functions fortransmitting/receiving signals through a wireless channel, such assignal band conversion, amplification, and the like. Specifically, theRF processor up-converts a baseband signal provided from the basebandprocessor into an RF band signal, transmits the same through an antenna,and down-converts an RF band signal received through the antenna into abaseband signal. The RF processor may include a transmission filter, areception filter, an amplifier, a mixer, an oscillator, adigital-to-analog converter (DAC), an analog-to-digital converter (ADC),and the like. The RF processor may perform MIMO and may receive multiplelayers when performing the MIMO operation. The baseband processorperforms a function of conversion between a baseband signal and a bitstring according to the physical layer specification of the system. Forexample, during data transmission, the baseband processor encodes andmodulates a transmission bit string, thereby generating complex symbols.In addition, during data reception, the baseband processor demodulatesand decodes a baseband signal provided from the RF processor, therebyrestoring a reception bit string.

The main processor 5A-04 controls the overall operations other thanmobile operation. The main processor 5A-04 process user input receivedfrom I/O unit 5A-05, stores data in the storage unit 5A-02, controls thecontroller 5A-01 for required mobile communication operations andforward user data to I/O unit (905).

I/O unit 5A-05 consists of equipment for inputting user data and foroutputting user data such as a microphone and a screen. I/O unit 5A-05performs inputting and outputting user data based on the mainprocessor's instruction.

FIG. 5B is a block diagram illustrating the configuration of a basestation according to the disclosure.

As illustrated in the diagram, the base station includes a controller5B-01, a storage 5 unit 5B-02, a transceiver 5B-03 and a backhaulinterface unit 5B-04.

The controller 5B-01 controls the overall operations of the main basestation. For example, the controller 5B-01 receives/transmits signalsthrough the transceiver 5B-03, or through the backhaul interface unit5B-04. In addition, the controller 5B-01 records and reads data in thestorage unit 5B-02. To this end, the controller 5B-01 may include atleast one processor. The controller controls transceiver, storage unitand backhaul interface such that base station operation illustrated inFIG. 3 are performed.

The storage unit 5B-02 stores data for operation of the main basestation, such as a basic program, an application program, andconfiguration information. Particularly, the storage unit 5B-02 maystore information regarding a bearer allocated to an accessed UE, ameasurement result reported from the accessed UE, and the like. Inaddition, the storage unit 5B-02 may store information serving as acriterion to deter mine whether to provide the UE with multi-connectionor to discontinue the same. In addition, the storage unit (5B-02)provides stored data at a request of the controller 5B-01.

The transceiver 5B-03 consists of a RF processor, a baseband processorand plurality of antennas. The RF processor performs functions fortransmitting/receiving signals through a wireless channel, such assignal band conversion, amplification, and the like. Specifically, theRF processor up-converts a baseband signal provided from the basebandprocessor into an RF band signal, transmits the same through an antenna,and down-converts an RF band signal received through the antenna into abaseband signal. The RF processor may include a transmission filter, areception filter, an amplifier, a mixer, an oscillator, a DAC, an ADC,and the like. The RF processor may perform a down link MIMO operation bytransmitting at least one layer. The baseband processor performs afunction of conversion between a baseband signal and a bit stringaccording to the physical layer specification of the first radio accesstechnology. For example, during data transmission, the basebandprocessor encodes and modulates a transmission bit string, therebygenerating complex symbols. In addition, during data reception, thebaseband processor demodulates and decodes a baseband signal providedfrom the RF processor, thereby restoring a reception bit string.

The backhaul interface unit 5B-04 provides an interface forcommunicating with other nodes inside the network. The backhaulinterface unit 5B-04 converts a bit string transmitted from the basestation to another node, for example, another base station or a corenetwork, into a physical signal, and converts a physical signal receivedfrom the other node into a bit string.

What is claimed is:
 1. A method by a terminal, the method comprising:selecting, by the terminal, a first cell; performing, by the terminal, afirst operation group if the terminal fails to acquire a MasterInformation Block (MIB) in the first cell, the first operation groupcomprises excluding the first cell as a candidate for cellselection/reselection and selecting another cell on the same frequencyas the first cell if a selection criteria are fulfilled; performing, bythe terminal, a second operation group if the terminal succeeds toacquire the MIB and a System Information Block1 (SIB1) in the first celland the MIB includes cellBarred set to barred and the SIB1 includes anintraFreqReselection set to NotAllowed, the second operation groupcomprises excluding the first cell as a candidate for cellselection/reselection and excluding another cell on the same frequencyof the first cell; and performing, by the terminal, a third operationgroup, if the terminal succeeds to acquire the MIB and the SIB1 in thefirst cell and the MIB includes cellBarred set to Notbarred and the SIB1includes the intraFreqReselection, the third operation group comprisesapplying the configuration included in a servingCellConfigCommon andapplying a specified PCCH configuration.
 2. The method of claim 1,wherein the terminal acquires the SIB1 in the first cell if the MIBacquired in the first cell includes cellBarred set to barred.
 3. Aterminal in a wireless communication system, the terminal comprising: atransceiver configured to transmit and receive a signal; and acontroller configured to control the transceiver to: select a firstcell; perform a first operation group if the terminal fails to acquire aMaster Information Block (MIB) in the first cell, the first operationgroup comprises excluding the first cell as a candidate for cellselection/reselection and selecting another cell on the same frequencyas the first cell if a selection criteria are fulfilled; perform asecond operation group if the terminal succeeds to acquire the MIB and aSystem Information Block1 (SIB1) in the first cell and the MIB includescellBarred set to barred and the SIB1 includes an intraFreqReselectionset to NotAllowed, the second operation group comprises excluding thefirst cell as a candidate for cell selection/reselection and excludinganother cell on the same frequency of the first cell; and perform athird operation group, if the terminal succeeds to acquire the MIB andthe SIB1 in the first cell and the MIB includes cellBarred set toNotbarred and the SIB1 includes the intraFreqReselection, the thirdoperation group comprises applying the configuration included in aservingCellConfigCommon and applying a specified PCCH configuration.